Gaming machines such as slot machines include a primary game and a bonus game. The game is begun when a coin, credit, coupon, cash or other financial instrument is input into the gaming machine. A player is then given an opportunity to place a wager, and the wager selection process can be relatively complicated depending on the type of game. For example, the player has to select the amount to wager, the number of paylines to play, and possibly even evaluate a paytable. The player then proceeds to “pull” the slot handle by pushing a button that initiates game play for the primary game.
During primary game play on a slot machine, for example, the reels spin and a player waits approximately six seconds for the outcome of the game session. During these six seconds, the underlying game accesses a random number generator (RNG) that generates a random output. The random output is then used to determine whether a player wins an award.
There are a variety of different awards that a player may win such as credits, a progressive, or the ability to play a bonus game. The player is awarded a prize based on the pay table and the resulting random number. With respect to a progressive jackpot, a portion of the players' wagers are placed in a “pot” and each player that is wagering on a gaming machine linked to the progressive jackpot has an opportunity to be awarded the progressive prize.
Another prize may also be awarded for a “bonus” game. The bonus game is a game-within-a-game, which may be triggered by a primary game prize. As such, a winning game outcome in the bonus game may result in awarding a bonus prize that is added to the prize won in the underlying primary game. Alternatively, a winning game outcome in the bonus game may result in multiplying the prize in the underlying primary game. A more detailed discussion of a bonus game feature is provided in commonly assigned U.S. Pat. No. 7,351,144 entitled BONUS GAME USING A SUBSET OF REELS that is hereby incorporated by reference.
Although a variety of different bonus features exists, previous implementation of bonus features in gaming machines have not permitted players to select or control the bonus results.